Question

explain an innate immune response that is related to receiving an incorrect blood type. Explain the steps of the response/reaction in detail.

Answer 1

Ans:

When a blood transfusion takes place and incompatible blood is given, the receiver's innate immune system treats the donor blood cells as a foreign invader and attacks them accordingly.The immune system attack can be so potential and massive that it may cause circulatory system collapse,kidney failure and ultimately lead to the receiver's death. Following are the steps of an immune response formed during the transfusion:

1. Detection of foreign material or the antigen by the immune system- When a an incorrect blood is transfused, the RBC of the donor cell and RBC of the receiver cell will mismatch.This mismatched RBC from donar will contain antigens,that are not present in the receivers RBC.The innate immunity system then detects this RBC as a foreign body and prepare itself to fight against this antigen.
2. Antigen is processed by the immune system- Antigens are engulfed by the macrophage,digested. This results in antigenic fragments presentation on the cell surface of macrophage along with histocompatibility complex. This is then binded by a T helper cells,which gets activated and further activates the B cell. T cells stimulates the B cell to grow and produce more of them.Some of these B cells then becomes plasma cells which produces the antibodies specific to the antigen that stimulated its production.
3. Immune system response formation for removing the antigen from the body - Since the RBC differs and the antigen is treated as a foreign body, a primary immune response is formed.The antibodies present in the receiver will bind to this antigen,hence coating the donor RBC.This results in RBC to agglutinate, which is then removed prematurely from the circulation by macrophage and phagocytose them.when a macrophages contain a receptor binding to antibodies and a receptor binding to complement fragments,it phagocytose the antiboy coated RBC after its removal from the circulation.Hence, RBC's that are incompatible by the body is destroyed rapidly after its binding by the antibodies.

In some cases, immune mediated transfusion reactions occurs in a person receiving incorrect blood type.This can occur immediately after the transfusion or may be delayed in some cases.The triggered immune response destroys the incompatible WBC's.